"You walked in and there was snow on the ground and blowing snow with snowmen and carolers," the source continued. "There was an upstairs part with a bar and then a tent below where the party was."

One of the event planners for the party posted a collage of scenes from the affair on his Instagram page Saturday afternoon, captioning the shot with, "Real snow, Christmas carolers, dirty Santa, drunk and passed out snowmen, ski lodge, 'smores bar, spiked hot chocolate...these are a few of my favorite things...the best holiday party, produced by @ExperienceNVE."

In the collage, there is a shot of Santa Claus sitting in a big red chair accompanied by a woman clad in a short green mini dress, a pool topped with snowflake reflections, and a couple of snowmen who had one two many.

And it's clear the media mogul knows how to through a killer party.

Back in October, Theron, Olivia Wilde and more celebs helped MacFarlane ring in his big 4-0 with another star-studded bash that started with a full-on orchestra performance and ended with a party outside in a huge tent (and then another after party at MacFarlane's home).